1 /* $NetBSD: dead_vnops.c,v 1.12 1994/12/16 03:18:03 mycroft Exp $ */ 2 3 /* 4 * Copyright (c) 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)dead_vnops.c 8.1 (Berkeley) 6/10/93 36 */ 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/time.h> 41 #include <sys/vnode.h> 42 #include <sys/errno.h> 43 #include <sys/namei.h> 44 #include <sys/buf.h> 45 46 /* 47 * Prototypes for dead operations on vnodes. 48 */ 49 int dead_badop(), 50 dead_ebadf(); 51 int dead_lookup __P((struct vop_lookup_args *)); 52 #define dead_create ((int (*) __P((struct vop_create_args *)))dead_badop) 53 #define dead_mknod ((int (*) __P((struct vop_mknod_args *)))dead_badop) 54 int dead_open __P((struct vop_open_args *)); 55 #define dead_close ((int (*) __P((struct vop_close_args *)))nullop) 56 #define dead_access ((int (*) __P((struct vop_access_args *)))dead_ebadf) 57 #define dead_getattr ((int (*) __P((struct vop_getattr_args *)))dead_ebadf) 58 #define dead_setattr ((int (*) __P((struct vop_setattr_args *)))dead_ebadf) 59 int dead_read __P((struct vop_read_args *)); 60 int dead_write __P((struct vop_write_args *)); 61 int dead_ioctl __P((struct vop_ioctl_args *)); 62 int dead_select __P((struct vop_select_args *)); 63 #define dead_mmap ((int (*) __P((struct vop_mmap_args *)))dead_badop) 64 #define dead_fsync ((int (*) __P((struct vop_fsync_args *)))nullop) 65 #define dead_seek ((int (*) __P((struct vop_seek_args *)))nullop) 66 #define dead_remove ((int (*) __P((struct vop_remove_args *)))dead_badop) 67 #define dead_link ((int (*) __P((struct vop_link_args *)))dead_badop) 68 #define dead_rename ((int (*) __P((struct vop_rename_args *)))dead_badop) 69 #define dead_mkdir ((int (*) __P((struct vop_mkdir_args *)))dead_badop) 70 #define dead_rmdir ((int (*) __P((struct vop_rmdir_args *)))dead_badop) 71 #define dead_symlink ((int (*) __P((struct vop_symlink_args *)))dead_badop) 72 #define dead_readdir ((int (*) __P((struct vop_readdir_args *)))dead_ebadf) 73 #define dead_readlink ((int (*) __P((struct vop_readlink_args *)))dead_ebadf) 74 #define dead_abortop ((int (*) __P((struct vop_abortop_args *)))dead_badop) 75 #define dead_inactive ((int (*) __P((struct vop_inactive_args *)))nullop) 76 #define dead_reclaim ((int (*) __P((struct vop_reclaim_args *)))nullop) 77 int dead_lock __P((struct vop_lock_args *)); 78 #define dead_unlock ((int (*) __P((struct vop_unlock_args *)))nullop) 79 int dead_bmap __P((struct vop_bmap_args *)); 80 int dead_strategy __P((struct vop_strategy_args *)); 81 int dead_print __P((struct vop_print_args *)); 82 #define dead_islocked ((int (*) __P((struct vop_islocked_args *)))nullop) 83 #define dead_pathconf ((int (*) __P((struct vop_pathconf_args *)))dead_ebadf) 84 #define dead_advlock ((int (*) __P((struct vop_advlock_args *)))dead_ebadf) 85 #define dead_blkatoff ((int (*) __P((struct vop_blkatoff_args *)))dead_badop) 86 #define dead_valloc ((int (*) __P((struct vop_valloc_args *)))dead_badop) 87 #define dead_vfree ((int (*) __P((struct vop_vfree_args *)))dead_badop) 88 #define dead_truncate ((int (*) __P((struct vop_truncate_args *)))nullop) 89 #define dead_update ((int (*) __P((struct vop_update_args *)))nullop) 90 #define dead_bwrite ((int (*) __P((struct vop_bwrite_args *)))nullop) 91 92 int (**dead_vnodeop_p)(); 93 struct vnodeopv_entry_desc dead_vnodeop_entries[] = { 94 { &vop_default_desc, vn_default_error }, 95 { &vop_lookup_desc, dead_lookup }, /* lookup */ 96 { &vop_create_desc, dead_create }, /* create */ 97 { &vop_mknod_desc, dead_mknod }, /* mknod */ 98 { &vop_open_desc, dead_open }, /* open */ 99 { &vop_close_desc, dead_close }, /* close */ 100 { &vop_access_desc, dead_access }, /* access */ 101 { &vop_getattr_desc, dead_getattr }, /* getattr */ 102 { &vop_setattr_desc, dead_setattr }, /* setattr */ 103 { &vop_read_desc, dead_read }, /* read */ 104 { &vop_write_desc, dead_write }, /* write */ 105 { &vop_ioctl_desc, dead_ioctl }, /* ioctl */ 106 { &vop_select_desc, dead_select }, /* select */ 107 { &vop_mmap_desc, dead_mmap }, /* mmap */ 108 { &vop_fsync_desc, dead_fsync }, /* fsync */ 109 { &vop_seek_desc, dead_seek }, /* seek */ 110 { &vop_remove_desc, dead_remove }, /* remove */ 111 { &vop_link_desc, dead_link }, /* link */ 112 { &vop_rename_desc, dead_rename }, /* rename */ 113 { &vop_mkdir_desc, dead_mkdir }, /* mkdir */ 114 { &vop_rmdir_desc, dead_rmdir }, /* rmdir */ 115 { &vop_symlink_desc, dead_symlink }, /* symlink */ 116 { &vop_readdir_desc, dead_readdir }, /* readdir */ 117 { &vop_readlink_desc, dead_readlink }, /* readlink */ 118 { &vop_abortop_desc, dead_abortop }, /* abortop */ 119 { &vop_inactive_desc, dead_inactive }, /* inactive */ 120 { &vop_reclaim_desc, dead_reclaim }, /* reclaim */ 121 { &vop_lock_desc, dead_lock }, /* lock */ 122 { &vop_unlock_desc, dead_unlock }, /* unlock */ 123 { &vop_bmap_desc, dead_bmap }, /* bmap */ 124 { &vop_strategy_desc, dead_strategy }, /* strategy */ 125 { &vop_print_desc, dead_print }, /* print */ 126 { &vop_islocked_desc, dead_islocked }, /* islocked */ 127 { &vop_pathconf_desc, dead_pathconf }, /* pathconf */ 128 { &vop_advlock_desc, dead_advlock }, /* advlock */ 129 { &vop_blkatoff_desc, dead_blkatoff }, /* blkatoff */ 130 { &vop_valloc_desc, dead_valloc }, /* valloc */ 131 { &vop_vfree_desc, dead_vfree }, /* vfree */ 132 { &vop_truncate_desc, dead_truncate }, /* truncate */ 133 { &vop_update_desc, dead_update }, /* update */ 134 { &vop_bwrite_desc, dead_bwrite }, /* bwrite */ 135 { (struct vnodeop_desc*)NULL, (int(*)())NULL } 136 }; 137 struct vnodeopv_desc dead_vnodeop_opv_desc = 138 { &dead_vnodeop_p, dead_vnodeop_entries }; 139 140 /* 141 * Trivial lookup routine that always fails. 142 */ 143 /* ARGSUSED */ 144 int 145 dead_lookup(ap) 146 struct vop_lookup_args /* { 147 struct vnode * a_dvp; 148 struct vnode ** a_vpp; 149 struct componentname * a_cnp; 150 } */ *ap; 151 { 152 153 *ap->a_vpp = NULL; 154 return (ENOTDIR); 155 } 156 157 /* 158 * Open always fails as if device did not exist. 159 */ 160 /* ARGSUSED */ 161 dead_open(ap) 162 struct vop_open_args /* { 163 struct vnode *a_vp; 164 int a_mode; 165 struct ucred *a_cred; 166 struct proc *a_p; 167 } */ *ap; 168 { 169 170 return (ENXIO); 171 } 172 173 /* 174 * Vnode op for read 175 */ 176 /* ARGSUSED */ 177 dead_read(ap) 178 struct vop_read_args /* { 179 struct vnode *a_vp; 180 struct uio *a_uio; 181 int a_ioflag; 182 struct ucred *a_cred; 183 } */ *ap; 184 { 185 186 if (chkvnlock(ap->a_vp)) 187 panic("dead_read: lock"); 188 /* 189 * Return EOF for character devices, EIO for others 190 */ 191 if (ap->a_vp->v_type != VCHR) 192 return (EIO); 193 return (0); 194 } 195 196 /* 197 * Vnode op for write 198 */ 199 /* ARGSUSED */ 200 dead_write(ap) 201 struct vop_write_args /* { 202 struct vnode *a_vp; 203 struct uio *a_uio; 204 int a_ioflag; 205 struct ucred *a_cred; 206 } */ *ap; 207 { 208 209 if (chkvnlock(ap->a_vp)) 210 panic("dead_write: lock"); 211 return (EIO); 212 } 213 214 /* 215 * Device ioctl operation. 216 */ 217 /* ARGSUSED */ 218 dead_ioctl(ap) 219 struct vop_ioctl_args /* { 220 struct vnode *a_vp; 221 u_long a_command; 222 caddr_t a_data; 223 int a_fflag; 224 struct ucred *a_cred; 225 struct proc *a_p; 226 } */ *ap; 227 { 228 229 if (!chkvnlock(ap->a_vp)) 230 return (EBADF); 231 return (VCALL(ap->a_vp, VOFFSET(vop_ioctl), ap)); 232 } 233 234 /* ARGSUSED */ 235 dead_select(ap) 236 struct vop_select_args /* { 237 struct vnode *a_vp; 238 int a_which; 239 int a_fflags; 240 struct ucred *a_cred; 241 struct proc *a_p; 242 } */ *ap; 243 { 244 245 /* 246 * Let the user find out that the descriptor is gone. 247 */ 248 return (1); 249 } 250 251 /* 252 * Just call the device strategy routine 253 */ 254 dead_strategy(ap) 255 struct vop_strategy_args /* { 256 struct buf *a_bp; 257 } */ *ap; 258 { 259 260 if (ap->a_bp->b_vp == NULL || !chkvnlock(ap->a_bp->b_vp)) { 261 ap->a_bp->b_flags |= B_ERROR; 262 biodone(ap->a_bp); 263 return (EIO); 264 } 265 return (VOP_STRATEGY(ap->a_bp)); 266 } 267 268 /* 269 * Wait until the vnode has finished changing state. 270 */ 271 dead_lock(ap) 272 struct vop_lock_args /* { 273 struct vnode *a_vp; 274 } */ *ap; 275 { 276 277 if (!chkvnlock(ap->a_vp)) 278 return (0); 279 return (VCALL(ap->a_vp, VOFFSET(vop_lock), ap)); 280 } 281 282 /* 283 * Wait until the vnode has finished changing state. 284 */ 285 dead_bmap(ap) 286 struct vop_bmap_args /* { 287 struct vnode *a_vp; 288 daddr_t a_bn; 289 struct vnode **a_vpp; 290 daddr_t *a_bnp; 291 int *a_runp; 292 } */ *ap; 293 { 294 295 if (!chkvnlock(ap->a_vp)) 296 return (EIO); 297 return (VOP_BMAP(ap->a_vp, ap->a_bn, ap->a_vpp, ap->a_bnp, ap->a_runp)); 298 } 299 300 /* 301 * Print out the contents of a dead vnode. 302 */ 303 /* ARGSUSED */ 304 dead_print(ap) 305 struct vop_print_args /* { 306 struct vnode *a_vp; 307 } */ *ap; 308 { 309 310 printf("tag VT_NON, dead vnode\n"); 311 } 312 313 /* 314 * Empty vnode failed operation 315 */ 316 dead_ebadf() 317 { 318 319 return (EBADF); 320 } 321 322 /* 323 * Empty vnode bad operation 324 */ 325 dead_badop() 326 { 327 328 panic("dead_badop called"); 329 /* NOTREACHED */ 330 } 331 332 /* 333 * Empty vnode null operation 334 */ 335 dead_nullop() 336 { 337 338 return (0); 339 } 340 341 /* 342 * We have to wait during times when the vnode is 343 * in a state of change. 344 */ 345 chkvnlock(vp) 346 register struct vnode *vp; 347 { 348 int locked = 0; 349 350 while (vp->v_flag & VXLOCK) { 351 vp->v_flag |= VXWANT; 352 sleep((caddr_t)vp, PINOD); 353 locked = 1; 354 } 355 return (locked); 356 } 357